Face masks



Aug. 27, 1963 L. A. GRUENEWAELDER 3,101 70 FACE MASKS Filed April 6,1959 QOQOQQ eeeqese v FIG. 5

. I 0 0 a 0 g 0 a) 6' 3% o 3g o 0330 Q @21 0 0 gm INVENTOR. Q a: 6 7 LOUA. GRUENEWAELDER FIG. 4 WW ATTORNEY thermoplastic synthetic resin.

United States Patent 3,101,709 FACE MASKS Lou A. Gruenewaelder, 6917Pershing Ave., University City, Mo. Filed Apr. 6, 1959, Ser. No. 804,4599 Claims. (Cl. 128-14-6) This invention relates to certain new anduseful improvements in face masks.

Ordinarily, doctors, nurses, and other hospital personnel, wear facemasks when performing their duties in operating rooms, contagiousdisease wards and the like. These face masks usually consist of nothingmore than a woven gauze pad which is strapped over the nose and mouthofthe wearer. Unfortunately, however, this type of face mask isfrequently too porous to serve effectively as a filter for trappingairborne bacteria or even toxic fumes with the result that under manyconditions of hospital use this type of face mask afiords little or noprotection. Special purpose face masks are available for filtering outhighly poisonous or toxic vapors, and these masks are highly effectiveand useful for certain purposes. However, a mask of this type isordinarily unsuitable for hospital use or for others who may beattending convalescent patients.

It is therefore, the primary object of the present invention to providea face mask which effectively filters out dust, vapors, fumes, airbornebacteria, and the like, thus preventing such elements from entering thenose, mouth, or respiratory system.

It is also an object of the present invention to provide a face mask ofthe type stated which is comfortable to wear and does not materiallyrestrict normal breathing.

It is an additional object of the present invention to provide a facemask of the type stated which is easy to clean and sterilize.

It is a further object of the present invention to provide a face maskof the type stated which is light in weight and relatively inexpensiveto manufacture.

It is another and more specific object of the present invention toprovide a face mask which includes a porous filtering element having afungicide dispersed therein so that airborne bacteria can be removed andrendered harmless.

With the above and other objects in view, my invention resides in thenovel features of form, construction, arrangement, and combination ofparts presently described and pointed out in the claims.

In the accompanying drawing (one sheet)- FIG. 1 is a perspective view ofa face mask constructed in accordance with and embodying the presentinvention and showing the face mask in position on the face of g thewearer;

FIG. 2 is a top plan view of the face mask;

FIG. 3 is a sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is an exploded perspective view of the face mask; and

FIG. 5 is a perspective view of the face mask.

Referring now in more detail and by reference charac-- ters to thedrawing, which illustrates a preferred embodiment of the presentinvention, A designates a face mask comprising a pair of rectangularplies 1, 2, of woven fabric and being provided on their inner faces 3,4, with a The plies 1, 2, are each provided with bench marks 5, 6, 7, 8,5', 6, 7', 8, and faces 3, 4, are facewise heat-sealed together with thebench marks 5, 6, 7, 8, 5', 6, 7', 8', respectively, in registration, soas to form a pocket 9 between the plies 1, 2. Each of the plies 1, 2, isalso provided with perforations 10, 11, which are so arranged that theywill be offset or staggered from each other when the plies 1, 2, areheat-sealed together.

Snugly disposed in the pocket 9' in overlying relation to saidperforations 10*, 11, is a thin, porous, wafer-like filtering element 12made of foamed polyurethane sponge. Preferably the vertical side marginsof the mask A are provided with short tucks t, t, thereby imparting adesirable degree of concavity to the mask A, so that it will more easilyconform to and fit over the mouth and nose of the user. This material iscapable of being formed into sponges having extremely small pores andis, therefore, highly effective as a filtering medium. However, itshould be understood that other porous cellular materials may be used infabricating the filtering element 12. In preparing the filtering element12, the polyurethane is foamed and cured in the conventional manner.However, in compounding the polyurethane plastisol prior to foaming, asmall amount, preferably 2% to 5% by weight, of a quaternary ammoniumcompound is added to the pl-astisol. Quaternary ammonium compounds arehighly active fungicides and have the property of destroying macro andmicro-organisms, such as airborne bacteria. Among the quaternaryammonium compounds which can be used in the present invention aredodecyl dimethyl benzyl ammonium naphthenate, cetyl dimethyl benzylammonium naphthenates, 9-octadecenyl dimethyl ethyl ammoniumnaphthenate, tetraethyl ammonium naphthenate, dimethyl ethyl propylammonium naphthenate, N- (lauric acid ester of colamino-formyl methyl)dimethyl ammonium naphthenate, and N-alkylbenzyl trimethyl ammoniumnaphthenates, such as N-dodecylbenzyl trimethyl ammonium naphthenate.One of the most useful and practical quaternary ammonium compounds andthe one found preferable for the present invention is di-isobutylphenoxy ethyl dimethyl benzyl ammonium chloride monohydrate, togetherwith a dimethyl silicone oil to impart heat resistance to the cells ofthe foam. For instance, when polyurethane foam is laundered, the hotWater tends to collapse the cells of the foam. The addition from 0.2% to1% by weight of a silicone will overcome this difiiculty. Of course, thesilicone can be omitted if the mask is to be used only a few times andthrown away without laundering. Consequently, when the polyurethane iscured, the quaternary ammonium napthenate will be completely andhomogeneously dispersed therein and the cells of the filtering element12 will be provided on their surfaces with an'active, nontoxic fungicideand bactericide.

It has also been found that other types of nontoxic, ac-' tivebactericides may be used; For example, less than 1% by weight of phenylmercuric acetate may be compounded with the polyurethane to provide aneffective filtering element 12.

Stitched,heat-sealed, or otherwise secured at the four corners of one ofthe plies 1, 2, are narrow tying straps 13, 14, 15, 16, which are of asufficient length to extend around'the head of the wearer as shown inFIG. 1.

In use, the face mask is placed over the face, as shown in FIG. 1, withthe filtering element 12 disposed over the nose' and mouth. Since theplies 1, 2, and filtering element 12 are flexible, they willsubstantially conform to the contour of the face. Moreover, the areas ofthe plies 1, 2, which are heat-sealed. together form an air imperviousbarrier as well as prevent any tearing or accidental separation of theplies 1, 2, and, therefore, effectively prevent air from entering thenose and mouth except through the filtering element 12. Moreover, sincetheperforations 10, 11, are staggered or offset from each other, thepath through which the air flows in the filtering element 12 is greaterthan would be the case if the perforations were in alignment.Consequently, it is possible to filter out a larger amount of foreignmatter from the air. Furthermore, all the air passage through thefiltering element will be exposed to the active bactericide withPatented Aug. 27, 1963 the result that many types of airborne bacteriawill be rendered harmless before entering the mouth and nose of theperson wearing the mask. In the care and feeding of newly born babies,as well as in surgical operating rooms where sterile conditions must bemaintained, face masks of the present invention prevent contamination ofthe sterile field by destroying bacteria exhaled by the wearer.

It will be apparent that filtering elements of the type used in the facemask A can be formed of many sizes and shapes and can be utilized asfilters in air conditioning systems in hospitals and the like.

It should be understood that changes and modifications in the form,construction, arrangement, and combination of the several parts of theface masks may be made and substituted for those herein shown anddescribed without departing from the nature and principle of myinvention.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

1. A face mask comprising a flexible sheet-like portion consisting oftwo substantially rectangular plies, each of which is provided with alayer of thermoplastic synthetic resin on its inner face, saidsheet-like portion being pro vided with a plurality of perforations,and'a porous filtering element containing less than 1% by weight ofphenyl mercuric acetate and being secured to said body portion andcovering said perforations, said body portion being substantially airimpervious except at said perforations so that air passing through saidbody portion will travel through said perforations and filteringelement.

2. A face mask comprising a flexible sheet-like body portion consistingof two substantially rectangular plies, each of which is provided with alayer of thermoplastic synthetic resin on its inner face, saidsheet-like portion being provided with a plurality of perforations, anda foamed-sponge filtering element containing a quaternary ammoniumnaphthenate and secured to said body portion over said perforations,said body portion being substantially air impervious except at saidperforations so that air passing through said body portion will travelthrough said perforations and filtering element.

3. A face mask comprising a flexible sheet-like body portion consistingof two substantially rectangular plies, each of which is provided with alayer of thermoplastic synthetic resin on its inner face, saidsheet-like portion being provided 'with a plurality of perforations, anda polyurethane sponge filtering element containing 2% to 5% by weight ofa quaternary ammonium naphthenate, said filtering element being securedto said body portion over said perforations, said body portion beingsubstantially air impervious except at said perforations so that airpassing through said body portion will travel through said perforationsand filtering element.

4. A face mask comprising a plurality of substantial-1y rectangularplies, each of which is provided with a plurality of perforations, theinner face of said plies each being provided with a layer ofthermoplastic synthetic resin, each of said plies having a short tuck atits vertical side margin to impart a degree of concavity, and a porousfiltering clement confined between the two plies, said filtering elementcontaining a quaternary ammonium naphthenate, said plies beingsubstantially air impervious except at said perforations so that airpassing through said plies will travel through said perforations andfiltering element.

5. A face mask comprising a plurality of substantially rectangularplies, each of which is provided with a plurality of perforations, theinner face of said plies each being provided with a layer ofthermoplastic synthetic resin, each of said plies having a short tuck atits vertical side margin to impart a degree of concavity, and apolyurethane sponge filtering element confined between the,

two plies and covering the perforations therein, said filter- 4 ingelement containing 2% to 5% by weight of a quaternary ammoniumnaphthenate, said plies being substantially air impervious except atsaid perforations so that air passing through said plies will travelthrough said perforations and filtering element.

6. A face mask comprising a pair of rectangular plies of woven fabricand being provided on its inner face with a thermoplastic syntheticresin, each of said plies having perforations so arranged to be offsetand staggered from each other, and a foamed polyurethane spongefiltering element interposed between said two plies and covering theperforations therein, said filtering element containing 2% to 5% byWeight of quaternary ammonium naphthenate, said plies beingsubstantially air impervious except at said perforations so that airpassing through said plies will travel through said perforations andfiltering element.

7. A face mask comprising a pair of rectangular plies of woven fabricand being provided on its inner face with a thermoplastic syntheticresin, each of said plies having perforations so arranged to be offsetand staggered from each other, and a foamed polyurethane spongefiltering element interposed between said two plies and covering theperforations therein, said filtering element containing 2% to 5% byWeight of di-isobut'yl phenoxy ethyl dimethyl benzyl ammonium chloridemonohydrate, said plies being substantially air impervious except atsaid perforations so that air passing through said plies will travelthrough said perforations and filtering element.

8. A face mask comprising a pair of rectangular plies of woven fabricand being provided on its inner face with a thermoplastic syntheticresin, each of said plies having perforations so arranged to be offsetand staggered from each other, and a foamed polyurethane spongefilteringelement interposed between said two plies and covering the perforationstherein, said filtering element containing 2% to 5% by weight ofdi-iso-butyl phenoxy ethyl dimethyl benzyl ammonium chloridemonohydrate, and 0.2% to 1% of a dimethyl silicone oil for impartingheat resistance to the sponge cells, said plies being substantially airimpervious except at said perforations so that air passing through saidplies will travel through said perforations and filtering element.

9. A face mask comprising a pair of rectangular plies of woven fabricand being provided on its inner face with a thermoplastic syntheticresin, each of said plies having perforations so arranged to be offsetand staggered from each other, and a foamed polyurethane spongefiltering element interposed between said two plies and covering theperforations therein, said filtering element containing a compound ofthe class consisting of dodecyl dimethyl benzyl -ammonium naphthen'ate,cetyl dimethyl benzyl ammonium naphthenates, 9-octadecenyl dimethylethyl ammonium naphthenate, .tetraethyl ammonium naphthenate, dimethylethyl propyl ammonium naphthenate, N (lauric acid ester ofcolarninoformyl methy-l) dimethyl ammonium naphthenate, N-dodecylben'zyltrimethyl ammonium naphthenate, and di-isobutyl phenoxy ethyl dimethylbenzyl ammonium chloride monohydrate.

References flited in the file of this patent UNITED STATES PATENTS535,718 Nagler Mar. 12, 1895 1,292,096 Schwartz Jan. 21, 1919 2,081,779Titus May 25, 1937 2,682,315 Evans June 29, 1954 2,733,776 Garelick Feb.7, 1956 2,770,241 Winkler Nov. 13, 1956 2,810,721 Lane Oct. 22, 1957

1. A FACE MASK COMPRISING A FLEXIBLE SHEET-LIKE PORTION CONSISTING OFTWO SUBSTANTIALLY RECTANGULAR PLIES, EACH OF WHICH IS PROVIDED WITH ALAYER OF THERMOPLASTIC SYNTHETIC RESIN ON ITS INNER FACE, SAIDSHEET-LIKE PORTION BEING PROVIDED WITH A PLURALITY OF PERFORATIONS, ANDA POROUS FILERING ELEMENT CONTAINING LESS THAN 1% BY WEIGHT OF PHENYLMERCURIC ACETATE AND BEING SECURED TO SAID BODY PORTION AND COVERINGSAID PERFORATIONS, SAID BODY PORTION BEING SUBSTANTIALLY AIR IMPERVIOUSEXCEPT AT SAID PERFORATIONS SO THAT AIR PASSING THROUGH SAID BODYPORTION WILL TRAVEL THROUGH SAID PERFORATIONS AND FILTERING ELEMENT.